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Analysis and Design of Soils and Terrain Digital Database (SOTER) Management System Based on Object-Oriented Method 被引量:4
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作者 ZHANGHAITAO ZHOUYONG +2 位作者 R.V.BIRNIE A.SIBBALD RENYI 《Pedosphere》 SCIE CAS CSCD 2003年第2期111-120,共10页
A SOTER management system was developed by analyzing, designing, programming, testing, repeated proceeding and progressing based on the object-oriented method. The function of the attribute database management is inhe... A SOTER management system was developed by analyzing, designing, programming, testing, repeated proceeding and progressing based on the object-oriented method. The function of the attribute database management is inherited and expanded in the new system. The integrity and security of the SOTER database are enhanced. The attribute database management, the spatial database management and the model base are integrated into SOTER based on the component object model (COM), and the graphical user interface (GUI) for Windows is used to interact with clients, thus being easy to create and maintain the SOTER, and convenient to promote the quantification and automation of soil information application. 展开更多
关键词 component object model database model OBJECT-ORIENTED SOTER
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Evaluation of the subseasonal forecast skill of surface soil moisture in the S2S database 被引量:3
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作者 ZHU Hanchen CHEN Haishan +1 位作者 ZHOU Yang DONG Xuan 《Atmospheric and Oceanic Science Letters》 CSCD 2019年第6期467-474,共8页
Based on the reforecasts from ve models of the Subseasonal to Seasonal(S2S)Prediction project,the S2S prediction skill of surface soil moisture(SM)over East Asia during May September is evaluated against ERA-Interim.R... Based on the reforecasts from ve models of the Subseasonal to Seasonal(S2S)Prediction project,the S2S prediction skill of surface soil moisture(SM)over East Asia during May September is evaluated against ERA-Interim.Results show that good prediction skill of SM is generally 510 forecast days prior over southern and northeastern China in the majority of models.Over the Tibetan Plateau and northwestern China,only the ECMWF model has good prediction skill 20 days in advance.Generally,better prediction skill tends to appear over wet regions rather than dry regions.In terms of the seasonal variation of SM prediction skill,some diffierences are noticed among the models,but most of them show good prediction skill during September.Furthermore,the significant positive correlation between the prediction skill of SM and ENSO index indicates modulation by ENSO of the S2S prediction of SM.When there is an El Nino(a La Nina)event,the SM prediction skill over eastern China tends to be high(low).Through evaluation of the S2S prediction skill of SM in these models,it is found that the prediction skill of SM is lower than that of most atmospheric variables in S2S forecasts.Therefore,more attention needs to be given to the S2S forecasting of land processes. 展开更多
关键词 soil moisture subseasonal to seasonal forecast skill evaluation East Asia
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Soil Database Management Software Development for Optimizing Land Resource Information Utilization to Support National Food Security
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作者 Rizatus Shofiyati Saefoel Bachri 《Journal of Geographic Information System》 2011年第3期211-216,共6页
Since land resource database development in 1987/1988, a large amount of digital data in spatial, tabular and metadata format has been collected and generated. There are some application softwares of soil database to ... Since land resource database development in 1987/1988, a large amount of digital data in spatial, tabular and metadata format has been collected and generated. There are some application softwares of soil database to manage such a large amount of data, i.e.: Side & Horizon (SHDE4), Soil Sample Analysis (SSA), and Land Unit in dbf file, while Site and Horizon is in DataEase formats. The database contains soil physics and chemical property data of each soil horizon from surface to effective soil depth, climate, land surface condi- tions, and other parameters required for soil classification. Currently, database management software for land resources is still based on DOS and is stand alone. The system is not efficient and effectively used as Agri- cultural Land Resource Information System. At present, as a key component of this system requires review and development of new database software is compatible with the development of information technology. This paper explains about development of interactive agricultural land resources information system for op- timizing land resources data utilization. Hopefully, the software can give contributions in national Agricul- tural Land Resources System Information development for supporting food security. 展开更多
关键词 soil database Software DEVELOPMENT LAND RESOURCES Information FOOD Security
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The competition between Bidens pilosa and Setaria viridis alters soil microbial composition and soil ecological function 被引量:1
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作者 Qiao Li Jianying Guo +1 位作者 Han Zhang Mengxin Zhao 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期267-282,共16页
Bidens pilosa is recognized as one of the major invasive plants in China.Its invasion has been associated with significant losses in agriculture,forestry,husbandry,and biodiversity.Soil ecosystems play an important ro... Bidens pilosa is recognized as one of the major invasive plants in China.Its invasion has been associated with significant losses in agriculture,forestry,husbandry,and biodiversity.Soil ecosystems play an important role in alien plant invasion.Microorganisms within the soil act as intermediaries between plants and soil ecological functions,playing a role in regulating soil enzyme activities and nutrient dynamics.Understanding the interactions between invasive plants,soil microorganisms,and soil ecological processes is vital for managing and mitigating the impacts of invasive species on the environment.In this study,we conducted a systematic analysis focusing on B.pilosa and Setaria viridis,a common native companion plant in the invaded area.To simulate the invasion process of B.pilosa,we constructed homogeneous plots consisting of B.pilosa and S.viridis grown separately as monocultures,as well as in mixtures.The rhizosphere and bulk soils were collected from the alien plant B.pilosa and the native plant S.viridis.In order to focus on the soil ecological functional mechanisms that contribute to the successful invasion of B.pilosa,we analyzed the effects of B.pilosa on the composition of soil microbial communities and soil ecological functions.The results showed that the biomass of B.pilosa increased by 27.51% and that of S.viridis was significantly reduced by 66.56%.The organic matter contents in the bulk and rhizosphere soils of B.pilosa were approximately 1.30 times those in the native plant soils.The TN and NO_(3)^(-)contents in the rhizosphere soil of B.pilosa were 1.30 to 2.71 times those in the native plant soils.The activities of acid phosphatase,alkaline phosphatase,and urease in the rhizosphere soil of B.pilosa were 1.98-2.25 times higher than in the native plant soils.Using high-throughput sequencing of the16S rRNA gene,we found that B.pilosa altered the composition of the soil microbial community.Specifically,many genera in Actinobacteria and Proteobacteria were enriched in B.pilosa soils.Further correlation analyses verified that these genera had significantly positive relationships with soil nutrients and enzyme activities.Plant biomass,soil p H,and the contents of organic matter,TN,NO_(3)^(-),TP,AP,TK,and AK were the main factors affecting soil microbial communities.This study showed that the invasion of B.pilosa led to significant alterations in the composition of the soil microbial communities.These changes were closely linked to modifications in plant traits as well as soil physical and chemical properties.Some microbial species related to C,N and P cycling were enriched in the soil invaded by B.pilosa.These findings provide additional support for the hypothesis of soil-microbe feedback in the successful invasion of alien plants.They also offer insights into the ecological mechanism by which soil microbes contribute to the successful invasion of B.pilosa.Overall,our research contributes to a better understanding of the complex interactions between invasive plants,soil microbial communities,and ecosystem dynamics. 展开更多
关键词 plant invasion Bidens pilosa soil microbial composition soil properties soil enzyme activities
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Biochar Decreases Soil Cadmium(Cd) Availability and Regulates Expression Levels of Cd Uptake/Transport-Related Genes to Reduce Cd Translocation in Rice 被引量:1
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作者 WANG Han HUANG Qina +3 位作者 ZHANG Yan SHAO Guosheng HU Yijun XU Youxiang 《Rice science》 SCIE CSCD 2024年第5期494-498,I0006-I0013,共13页
Biochar has been used as a soil amendment for heavy metal-contaminated soils, and it has the potential to mitigate Cd accumulation in plants. In this study, we used rice straw biochar(RSB) and kitchen waste biochar(KW... Biochar has been used as a soil amendment for heavy metal-contaminated soils, and it has the potential to mitigate Cd accumulation in plants. In this study, we used rice straw biochar(RSB) and kitchen waste biochar(KWB) to clarify the effect of biochar on Cd-contaminated neutral soil, the physiological responses to biochar application, and the gene regulatory networks in a rice genotype. 展开更多
关键词 soil STRAW soils
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Subsoil tillage enhances wheat productivity,soil organic carbon and available nutrient status in dryland fields 被引量:1
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作者 Qiuyan Yan Linjia Wu +6 位作者 Fei Dong Shuangdui Yan Feng Li Yaqin Jia Jiancheng Zhang Ruifu Zhang Xiao Huang 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期251-266,共16页
Tillage practices during the fallow period benefit water storage and yield in dryland wheat crops.However,there is currently no clarity on the responses of soil organic carbon(SOC),total nitrogen(TN),and available nut... Tillage practices during the fallow period benefit water storage and yield in dryland wheat crops.However,there is currently no clarity on the responses of soil organic carbon(SOC),total nitrogen(TN),and available nutrients to tillage practices within the growing season.This study evaluated the effects of three tillage practices(NT,no tillage;SS,subsoil tillage;DT,deep tillage)over five years on soil physicochemical properties.Soil samples at harvest stage from the fifth year were analyzed to determine the soil aggregate and aggregate-associated C and N fractions.The results indicated that SS and DT improved grain yield,straw biomass and straw carbon return of wheat compared with NT.In contrast to DT and NT,SS favored SOC and TN concentrations and stocks by increasing the soil organic carbon sequestration rate(SOCSR)and soil nitrogen sequestration rate(TNSR)in the 0-40 cm layer.Higher SOC levels under SS and NT were associated with greater aggregate-associated C fractions,while TN was positively associated with soluble organic nitrogen(SON).Compared with DT,the NT and SS treatments improved soil available nutrients in the 0-20 cm layer.These findings suggest that SS is an excellent practice for increasing soil carbon,nitrogen and nutrient availability in dryland wheat fields in North China. 展开更多
关键词 TILLAGE dryland wheat fields soil aggregate size soil nutrients soil carbon and nitrogen fractions
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A dynamic soil freezing characteristic curve model for frozen soil 被引量:1
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作者 Xiaokang Li Xu Li Jiankun Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期3339-3352,共14页
The soil freezing characteristic curve(SFCC)plays a fundamental role in comprehending thermohydraulic behavior and numerical simulation of frozen soil.This study proposes a dynamic model to uniformly express SFCCs ami... The soil freezing characteristic curve(SFCC)plays a fundamental role in comprehending thermohydraulic behavior and numerical simulation of frozen soil.This study proposes a dynamic model to uniformly express SFCCs amidst varying total water contents throughout the freezing-thawing process.Firstly,a general model is proposed,wherein the unfrozen water content at arbitrary temperature is determined as the lesser of the current total water content and the reference value derived from saturated SFCC.The dynamic performance of this model is verified through test data.Subsequently,in accordance with electric double layer(EDL)theory,the theoretical residual and minimum temperatures in SFCC are calculated to be-14.5℃to-20℃for clay particles and-260℃,respectively.To ensure that the SFCC curve ends at minimum temperature,a correction function is introduced into the general model.Furthermore,a simplified dynamic model is proposed and investigated,necessitating only three parameters inherited from the general model.Additionally,both general and simplified models are evaluated based on a test database and proven to fit the test data exactly across the entire temperature range.Typical recommended parameter values for various types of soils are summarized.Overall,this study provides not only a theoretical basis for most empirical equations but also proposes a new and more general equation to describe the SFCC. 展开更多
关键词 Frozen soils Unsaturated soils soil freezing characteristic curve(SFCC) Mathematic models
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A Large Scale GIS Geodatabase of Soil Parameters Supporting the Modeling of Conservation Practice Alternatives in the United States
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作者 Mauro Di Luzio Mike J. White +2 位作者 Jeffrey G. Arnold Jimmy R. Williams James R. Kiniry 《Journal of Geographic Information System》 2017年第3期267-278,共12页
Water quality modeling requires across-scale support of combined digital soil elements and simulation parameters. This paper presents the unprecedented development of a large spatial scale (1:250,000) ArcGIS geodataba... Water quality modeling requires across-scale support of combined digital soil elements and simulation parameters. This paper presents the unprecedented development of a large spatial scale (1:250,000) ArcGIS geodatabase coverage designed as a functional repository of soil-parameters for modeling and comparison of water quality outcomes in the United States. The set of target models include: SWAT (Soil and Water Assessment Tool), APEX (Agricultural Policy Environmental Extender), and ALMANAC (Agricultural Land Management Alternatives with Numerical Assessment Criteria). This development relies on the Digital General Soil Map (DGSM) as the source of soil information, and leverages on architectural design and associated tools created for a companion product at higher resolution from which also was extended a procedure for refilling a large number of missing derived parameters. Outlined by regional watershed layouts and supported by GIS land use layers, the core product is developed using the File Geodatabase (FGDB) data structure, which brings, via customized Python-based tools, the data directly into geoprocessing workflows. The FGDB implement efficiently stores spatial soil features, tabular model elements and linked relationships, while seamlessly providing the environment for the extraction, spatial analysis, and mapping of the models’ parameters. As an alternative, the composing spatial elements, polygons and multi-resolution rasters, and the models’ elements are offered as a file-folder system of data with completely Open Source formats. Finally, this geographic database coverage provides support for the traditional large-scale and harmonized application of the models as well as an alternative to the higher resolution companion for areas where this information is still under development. 展开更多
关键词 GEOdatabase soil SWAT APEX ALMANAC
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Straw return increases crop production by improving soil organic carbon sequestration and soil aggregation in a long-term wheat-cotton cropping system 被引量:2
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作者 Changqin Yang Xiaojing Wang +6 位作者 Jianan Li Guowei Zhang Hongmei Shu Wei Hu Huanyong Han Ruixian Liu Zichun Guo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期669-679,共11页
Straw return is a promising strategy for managing soil organic carbon(SOC)and improving yield stability.However,the optimal straw return strategy for sustainable crop production in the wheat(Triticum aestivum L.)-cott... Straw return is a promising strategy for managing soil organic carbon(SOC)and improving yield stability.However,the optimal straw return strategy for sustainable crop production in the wheat(Triticum aestivum L.)-cotton(Gossypium hirsutum L.)cropping system remains uncertain.The objective of this study was to quantify the long-term(10 years)impact of carbon(C)input on SOC sequestration,soil aggregation and crop yields in a wheat-cotton cropping system in the Yangtze River Valley,China.Five treatments were arranged with a single-factor randomized design as follows:no straw return(Control),return of wheat straw only(Wt),return of cotton straw only(Ct),return of 50%wheat and 50%cotton straw(Wh-Ch)and return of 100%wheat and 100%cotton straw(Wt-Ct).In comparison to the Control,the SOC content increased by 8.4 to 20.2%under straw return.A significant linear positive correlation between SOC sequestration and C input(1.42-7.19 Mg ha^(−1)yr^(−1))(P<0.05)was detected.The percentages of aggregates of sizes>2 and 1-2 mm at the 0-20 cm soil depth were also significantly elevated under straw return,with the greatest increase of the aggregate stability in the Wt-Ct treatment(28.1%).The average wheat yields increased by 12.4-36.0%and cotton yields increased by 29.4-73.7%,and significantly linear positive correlations were also detected between C input and the yields of wheat and cotton.The average sustainable yield index(SYI)reached a maximum value of 0.69 when the C input was 7.08 Mg ha^(−1)yr^(−1),which was close to the maximum value(SYI of 0.69,C input of 7.19 Mg ha^(−1)yr^(-1))in the Wt-Ct treatment.Overall,the return of both wheat and cotton straw was the best strategy for improving SOC sequestration,soil aggregation,yields and their sustainability in the wheat-cotton rotation system. 展开更多
关键词 straw return crop yields SOC soil aggregates wheat-cotton cropping system
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Assessment of soil erosion in the Irga watershed on the eastern edge of the Chota Nagpur Plateau,India 被引量:1
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作者 Ratan PAL Buddhadev HEMBRAM Narayan Chandra JANA 《Regional Sustainability》 2024年第1期54-68,共15页
Human activities to improve the quality of life have accelerated the natural rate of soil erosion.In turn,these natural disasters have taken a great impact on humans.Human activities,particularly the conversion of veg... Human activities to improve the quality of life have accelerated the natural rate of soil erosion.In turn,these natural disasters have taken a great impact on humans.Human activities,particularly the conversion of vegetated land into agricultural land and built-up area,stand out as primary contributors to soil erosion.The present study investigated the risk of soil erosion in the Irga watershed located on the eastern fringe of the Chota Nagpur Plateau in Jharkhand,India,which is dominated by sandy loam and sandy clay loam soil with low soil organic carbon(SOC)content.The study used the Revised Universal Soil Loss Equation(RUSLE)and Geographical Information System(GIS)technique to determine the rate of soil erosion.The five parameters(rainfall-runoff erosivity(R)factor,soil erodibility(K)factor,slope length and steepness(LS)factor,cover-management(C)factor,and support practice(P)factor)of the RUSLE were applied to present a more accurate distribution characteristic of soil erosion in the Irga watershed.The result shows that the R factor is positively correlated with rainfall and follows the same distribution pattern as the rainfall.The K factor values in the northern part of the study area are relatively low,while they are relatively high in the southern part.The mean value of the LS factor is 2.74,which is low due to the flat terrain of the Irga watershed.There is a negative linear correlation between Normalized Difference Vegetation Index(NDVI)and the C factor,and the high values of the C factor are observed in places with low NDVI.The mean value of the P factor is 0.210,with a range from 0.000 to 1.000.After calculating all parameters,we obtained the average soil erosion rate of 1.43 t/(hm^(2)•a),with the highest rate reaching as high as 32.71 t/(hm^(2)•a).Therefore,the study area faces a low risk of soil erosion.However,preventative measures are essential to avoid future damage to productive and constructive activities caused by soil erosion.This study also identifies the spatial distribution of soil erosion rate,which will help policy-makers to implement targeted soil erosion control measures. 展开更多
关键词 soil erosion soil organic carbon Rainfall-runoff erosivity factor soil erodibility factor Slope length and steepness factor Cover-management factor Support practice factor Irga watershed
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A dynamic database of solid-state electrolyte(DDSE)picturing all-solid-state batteries 被引量:1
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作者 Fangling Yang Egon Campos dos Santos +5 位作者 Xue Jia Ryuhei Sato Kazuaki Kisu Yusuke Hashimoto Shin-ichi Orimo Hao Li 《Nano Materials Science》 EI CAS CSCD 2024年第2期256-262,共7页
All-solid-state batteries(ASSBs)are a class of safer and higher-energy-density materials compared to conventional devices,from which solid-state electrolytes(SSEs)are their essential components.To date,investigations ... All-solid-state batteries(ASSBs)are a class of safer and higher-energy-density materials compared to conventional devices,from which solid-state electrolytes(SSEs)are their essential components.To date,investigations to search for high ion-conducting solid-state electrolytes have attracted broad concern.However,obtaining SSEs with high ionic conductivity is challenging due to the complex structural information and the less-explored structure-performance relationship.To provide a solution to these challenges,developing a database containing typical SSEs from available experimental reports would be a new avenue to understand the structureperformance relationships and find out new design guidelines for reasonable SSEs.Herein,a dynamic experimental database containing>600 materials was developed in a wide range of temperatures(132.40–1261.60 K),including mono-and divalent cations(e.g.,Li^(+),Na^(+),K^(+),Ag^(+),Ca^(2+),Mg^(2+),and Zn^(2+))and various types of anions(e.g.,halide,hydride,sulfide,and oxide).Data-mining was conducted to explore the relationships among different variates(e.g.,transport ion,composition,activation energy,and conductivity).Overall,we expect that this database can provide essential guidelines for the design and development of high-performance SSEs in ASSB applications.This database is dynamically updated,which can be accessed via our open-source online system. 展开更多
关键词 Solid-state electrolyte(SSE) All-solid-state battery(ASSB) Ionic conductivity Dynamic database Machine learning
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Manure substitution improves maize yield by promoting soil fertility and mediating the microbial community in lime concretion black soil 被引量:1
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作者 Minghui Cao Yan Duan +6 位作者 Minghao Li Caiguo Tang Wenjie Kan Jiangye Li Huilan Zhang Wenling Zhong Lifang Wu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期698-710,共13页
Synthetic nitrogen(N)fertilizer has made a great contribution to the improvement of soil fertility and productivity,but excessive application of synthetic N fertilizer may cause agroecosystem risks,such as soil acidif... Synthetic nitrogen(N)fertilizer has made a great contribution to the improvement of soil fertility and productivity,but excessive application of synthetic N fertilizer may cause agroecosystem risks,such as soil acidification,groundwater contamination and biodiversity reduction.Meanwhile,organic substitution has received increasing attention for its ecologically and environmentally friendly and productivity benefits.However,the linkages between manure substitution,crop yield and the underlying microbial mechanisms remain uncertain.To bridge this gap,a three-year field experiment was conducted with five fertilization regimes:i)Control,non-fertilization;CF,conventional synthetic fertilizer application;CF_(1/2)M_(1/2),1/2 N input via synthetic fertilizer and 1/2 N input via manure;CF_(1/4)M_(3/4),1/4 N input synthetic fertilizer and 3/4 N input via manure;M,manure application.All fertilization treatments were designed to have equal N input.Our results showed that all manure substituted treatments achieved high soil fertility indexes(SFI)and productivities by increasing the soil organic carbon(SOC),total N(TN)and available phosphorus(AP)concentrations,and by altering the bacterial community diversity and composition compared with CF.SOC,AP,and the soil C:N ratio were mainly responsible for microbial community variations.The co-occurrence network revealed that SOC and AP had strong positive associations with Rhodospirillales and Burkholderiales,while TN and C:N ratio had positive and negative associations with Micromonosporaceae,respectively.These specific taxa are implicated in soil macroelement turnover.Random Forest analysis predicted that both biotic(bacterial composition and Micromonosporaceae)and abiotic(AP,SOC,SFI,and TN)factors had significant effects on crop yield.The present work strengthens our understanding of the effects of manure substitution on crop yield and provides theoretical support for optimizing fertilization strategies. 展开更多
关键词 FERTILIZATION manure substitution soil fertility maize yield bacterial community
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Knowledge Map of Soil Nutrient Migration Analysis Based on WOS (Web of Science) Database
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作者 Jiafeng Wang Jingsheng Chen +2 位作者 Qiuliang Cai Jinsheng Huang Liuqiang Zhou 《Agricultural Sciences》 CAS 2023年第3期398-421,共24页
It is important to understand the research trends and hotspots of global soil nutrient migration and control. Based on the core collection of WOS (Web of Science), citespace knowledge map analysis tool was used to ana... It is important to understand the research trends and hotspots of global soil nutrient migration and control. Based on the core collection of WOS (Web of Science), citespace knowledge map analysis tool was used to analyze the number of publications, cooperation networks, disciplines, research hotspots and frontier trends on nutrient migration in soil. The results showed that: the number of publications on the study of soil nutrient migration showed a good growth from 1990 to 2021. 173 countries had cooperative relationships. The number of articles published in the United States and China was significantly higher than that in other countries, while Chinese Academy of Sciences was the institution with the largest number of publications. It was a comprehensive system that permeates with agriculture, environmental science, botany and other disciplines. The research of nutrient migration in soil mainly focused on the measures of microbial community in different land types to promote nutrient transformation, improve soil fertility and reduce nutrient loss. In the future, the research trends will be the management measures of soil nutrient loss, the relationship between the change of soil nutrient and plant community diversity, and the remediation of agricultural contaminated soil. Through the above analysis, there was an overall understanding of soil nutrient migration. The research on nutrient migration may continue to increase in the future. It is suggested that Chinese research institutions, teams and universities need to strengthen international cooperation, and speed up their integration with the international community. 展开更多
关键词 CiteSpace soil Nutrients Visual Analysis Research Progress Nutrient Migration
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Enhancing Deep Learning Soil Moisture Forecasting Models by Integrating Physics-based Models 被引量:1
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作者 Lu LI Yongjiu DAI +5 位作者 Zhongwang WEI Wei SHANGGUAN Nan WEI Yonggen ZHANG Qingliang LI Xian-Xiang LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第7期1326-1341,共16页
Accurate soil moisture(SM)prediction is critical for understanding hydrological processes.Physics-based(PB)models exhibit large uncertainties in SM predictions arising from uncertain parameterizations and insufficient... Accurate soil moisture(SM)prediction is critical for understanding hydrological processes.Physics-based(PB)models exhibit large uncertainties in SM predictions arising from uncertain parameterizations and insufficient representation of land-surface processes.In addition to PB models,deep learning(DL)models have been widely used in SM predictions recently.However,few pure DL models have notably high success rates due to lacking physical information.Thus,we developed hybrid models to effectively integrate the outputs of PB models into DL models to improve SM predictions.To this end,we first developed a hybrid model based on the attention mechanism to take advantage of PB models at each forecast time scale(attention model).We further built an ensemble model that combined the advantages of different hybrid schemes(ensemble model).We utilized SM forecasts from the Global Forecast System to enhance the convolutional long short-term memory(ConvLSTM)model for 1–16 days of SM predictions.The performances of the proposed hybrid models were investigated and compared with two existing hybrid models.The results showed that the attention model could leverage benefits of PB models and achieved the best predictability of drought events among the different hybrid models.Moreover,the ensemble model performed best among all hybrid models at all forecast time scales and different soil conditions.It is highlighted that the ensemble model outperformed the pure DL model over 79.5%of in situ stations for 16-day predictions.These findings suggest that our proposed hybrid models can adequately exploit the benefits of PB model outputs to aid DL models in making SM predictions. 展开更多
关键词 soil moisture forecasting hybrid model deep learning ConvLSTM attention mechanism
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Time-lagged Effects of the Spring Atmospheric Heat Source over the Tibetan Plateau on Summer Precipitation in Northeast China during 1961–2020:Role of Soil Moisture 被引量:1
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作者 Yizhe HAN Dabang JIANG +2 位作者 Dong SI Yaoming MA Weiqiang MA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1527-1538,共12页
The spring atmospheric heat source(AHS)over the Tibetan Plateau(TP)has been suggested to affect the Asian summer monsoon and summer precipitation over South China.However,its influence on the summer precipitation in N... The spring atmospheric heat source(AHS)over the Tibetan Plateau(TP)has been suggested to affect the Asian summer monsoon and summer precipitation over South China.However,its influence on the summer precipitation in Northeast China(NEC)remains unknown.The connection between spring TP AHS and subsequent summer precipitation over NEC from 1961 to 2020 is analyzed in this study.Results illustrate that stronger spring TP AHS can enhance subsequent summer NEC precipitation,and higher soil moisture in the Yellow River Valley-North China region(YRVNC)acts as a bridge.During spring,the strong TP AHS could strengthen the transportation of water vapor to East China and lead to excessive rainfall in the YRVNC.Thus,soil moisture increases,which regulates local thermal conditions by decreasing local surface skin temperature and sensible heat.Owing to the memory of soil moisture,the lower spring sensible heat over the YRVNC can last until mid-summer,decrease the land–sea thermal contrast,and weaken the southerly winds over the East Asia–western Pacific region and convective activities over the South China Sea and tropical western Pacific.This modulates the East Asia–Pacific teleconnection pattern,which leads to a cyclonic anomaly and excessive summer precipitation over NEC. 展开更多
关键词 Tibetan Plateau atmospheric heat source Northeast China summer precipitation soil moisture
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Semi-analytical solution for drained expansion analysis of a hollow cylinder of critical state soils 被引量:1
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作者 He Yang Jialiang Zhang +1 位作者 Haisui Yu Peizhi Zhuang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2326-2340,共15页
The expansion of a thick-walled hollow cylinder in soil is of non-self-similar nature that the stress/deformation paths are not the same for different soil material points.As a result,this problem cannot be solved by ... The expansion of a thick-walled hollow cylinder in soil is of non-self-similar nature that the stress/deformation paths are not the same for different soil material points.As a result,this problem cannot be solved by the common self-similar-based similarity techniques.This paper proposes a novel,exact solution for rigorous drained expansion analysis of a hollow cylinder of critical state soils.Considering stress-dependent elastic moduli of soils,new analytical stress and displacement solutions for the nonself-similar problem are developed taking the small strain assumption in the elastic zone.In the plastic zone,the cavity expansion response is formulated into a set of first-order partial differential equations(PDEs)with the combination use of Eulerian and Lagrangian descriptions,and a novel solution algorithm is developed to efficiently solve this complex boundary value problem.The solution is presented in a general form and thus can be useful for a wide range of soils.With the new solution,the non-self-similar nature induced by the finite outer boundary is clearly demonstrated and highlighted,which is found to be greatly different to the behaviour of cavity expansion in infinite soil mass.The present solution may serve as a benchmark for verifying the performance of advanced numerical techniques with critical state soil models and be used to capture the finite boundary effect for pressuremeter tests in small-sized calibration chambers. 展开更多
关键词 Cavity expansion Drained analysis Boundary effect Critical state soil Non-self-similar Eulerian-Lagrangian approach
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Impact of mica on geotechnical behavior of weathered granitic soil using macro and micro investigations 被引量:1
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作者 Xianwei Zhang Xinyu Liu +3 位作者 Haodong Gao Gang Wang Ran An Zhu Liang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2250-2266,共17页
The micaceous weathered granitic soil(WGS)is frequently encountered in civil engineering worldwide,unfortunately little information is available regarding how mica affects the physico-mechanical behaviors of WGS.This ... The micaceous weathered granitic soil(WGS)is frequently encountered in civil engineering worldwide,unfortunately little information is available regarding how mica affects the physico-mechanical behaviors of WGS.This study prepares reconstituted WGS with different mica contents by removing natural mica in theWGS,and then mixes it with commercial mica powders.The geotechnical behavior as well as the microstructures of the mixtures are characterized.The addition of mica enables the physical indices of WGS to be specific combinations of coarser gradation and high permeability but high Atterberg limits.However,high mica content in WGS was found to be associated with undesirable mechanical properties,including increased compressibility,disintegration,and swelling potential,as well as poor compactability and low effective frictional angle.Microstructural analysis indicates that the influence of mica on the responses of mixtures originates from the intrinsic nature of mica as well as the particle packing being formed withinWGS.Mica exists in the mixture as stacks of plates that form a spongy structure with high compressibility and swelling potential.Pores among the plates give the soil high water retention and high Atterberg limits.Large pores are also generated by soil particles with bridging packing,which enhances the permeability and water-soil interactions upon immersion.This study provides a microlevel understanding of how mica dominates the behavior of WGS and provides new insights into the effective stabilization and improvement of micaceous soils. 展开更多
关键词 Weathered granitic soil(WGS) MICA Microstructure Physical properties Mechanical properties Mechanism
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Formation of Tianwen-1 landing crater and mechanical properties of Martian soil near the landing site 被引量:1
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作者 Xinshuo Chen Zhaobin Zhang +7 位作者 Juan Li Shouding Li Tao Xu Bo Zheng Xiukuo Sun Yanfang Wu Yiming Diao Xiao Li 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第9期1293-1303,共11页
After landing in the Utopia Planitia,Tianwen-1 formed the deepest landing crater on Mars,approximately 40 cm deep,exposing precious information about the mechanical properties of Martian soil.We established numerical ... After landing in the Utopia Planitia,Tianwen-1 formed the deepest landing crater on Mars,approximately 40 cm deep,exposing precious information about the mechanical properties of Martian soil.We established numerical models for the plume-surface interaction(PSI)and the crater formation based on Computational Fluid Dynamics(CFD)methods and the erosion model modified from Roberts’Theory.Comparative studies of cases were conducted with different nozzle heights and soil mechanical properties.The increase in cohesion and internal friction angle leads to a decrease in erosion rate and maximum crater depth,with the cohesion having a greater impact.The influence of the nozzle height is not clear,as it interacts with the position of the Shock Diamond to jointly control the erosion process.Furthermore,we categorized the evolution of landing craters into the dispersive and the concentrated erosion modes based on the morphological characteristics.Finally,we estimated the upper limits of the Martian soil’s mechanical properties near Tianwen-1 landing site,with the cohesion ranging from 2612 to 2042 Pa and internal friction angle from 25°to 41°. 展开更多
关键词 Tianwen-1 Plume-surface interaction Landing crater formation Martian soil mechanical properties Numerical simulation
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Physical and mechanical properties and microstructures of submarine soils in the Yellow Sea 被引量:1
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作者 Zhuangcai Tian Yihua Chang +6 位作者 Sichao Chen Gengchen Wang Yanhong Hu Chuan Guo Lei Jia Lei Song Jianhua Yue 《Deep Underground Science and Engineering》 2024年第2期197-206,共10页
In recent years,the exploration of seabed has been intensified,but the submarine soils of silt and sand in the Yellow Sea area have not been well investigated so far.In this study,the physical and mechanical propertie... In recent years,the exploration of seabed has been intensified,but the submarine soils of silt and sand in the Yellow Sea area have not been well investigated so far.In this study,the physical and mechanical properties of silt and sand from the Yellow Sea were measured using a direct shear apparatus and their microstructures were observed using a scanning electron microscope.The test results suggest that the shear strength of silt and sand increases linearly with the increase of normal stress.Based on the direct shear test,the scanning electron microscope was used to observe the section surface of sand.It is observed that the section surface becomes rough,with many“V”‐shaped cracks.Many particles appear on the surface of the silt structure and tend to be disintegrated.The X‐ray diffraction experiment reveals that the sand and silt have different compositions.The shear strength of sand is slightly greater than that of silt under high stress,which is related to the shape of soil particles and the mineral composition.These results can be a reference for further study of other soils in the Yellow Sea;meanwhile,they can serve as soil parameters for the stability and durability analyses of offshore infrastructure construction. 展开更多
关键词 direct shear test MICROSCOPE physical properties submarine soil Yellow Sea
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Analytical model for predicting time-dependent lateral deformation of geosynthetics-reinforced soil walls with modular block facing 被引量:1
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作者 Luqiang Ding Chengzhi Xiao Feilong Cui 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期711-725,共15页
To date,few models are available in the literature to consider the creep behavior of geosynthetics when predicting the lateral deformation(d)of geosynthetics-reinforced soil(GRS)retaining walls.In this study,a general... To date,few models are available in the literature to consider the creep behavior of geosynthetics when predicting the lateral deformation(d)of geosynthetics-reinforced soil(GRS)retaining walls.In this study,a general hyperbolic creep model was first introduced to describe the long-term deformation of geosynthetics,which is a function of elapsed time and two empirical parameters a and b.The conventional creep tests with three different tensile loads(Pr)were conducted on two uniaxial geogrids to determine their creep behavior,as well as the a-Pr and b-Pr relationships.The test results show that increasing Pr accelerates the development of creep deformation for both geogrids.Meanwhile,a and b respectively show exponential and negatively linear relationships with Pr,which were confirmed by abundant experimental data available in other studies.Based on the above creep model and relationships,an accurate and reliable analytical model was then proposed for predicting the time-dependent d of GRS walls with modular block facing,which was further validated using a relevant numerical investigation from the previous literature.Performance evaluation and comparison of the proposed model with six available prediction models were performed.Then a parametric study was carried out to evaluate the effects of wall height,vertical spacing of geogrids,unit weight and internal friction angle of backfills,and factor of safety against pullout on d at the end of construction and 5 years afterwards.The findings show that the creep effect not only promotes d but also raises the elevation of the maximum d along the wall height.Finally,the limitations and application prospects of the proposed model were discussed and analyzed. 展开更多
关键词 GEOSYNTHETICS Creep behavior Geosynthetics-reinforced soil(GRS)walls Lateral deformation Analytical model
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